1. Technical Field
The present invention relates to a linear actuator and, in particular, to a linear actuator effecting quick releasement by a clutch member.
2. Related Art
Linear actuators are widely used for closing/opening doors or elevating/lowering hospital beds. The conventional linear actuator usually includes a motor and an actuator block threadedly connected to a screw rod. The actuator block is restricted in a linear track and is linearly movable in the track upon rotation of the screw rod driven by the motor. The actuator block can be connected by a rod to a to-be-pushed object for pushing it.
However, the above-mentioned structure can only move the to-be-pushed object by driving the motor. Therefore, when it is used for elevating/lowering hospital beds, it cannot quickly lower the beds for medical workers to save patients in emergencies.
In view of the foregoing, the inventor made various studies to improve the above-mentioned problems to realize the improvements, on the basis of which the present invention is accomplished.